Electric-motor starting and stopping device.



No. 788,819. PATENTED MAY 2, 1905.

J. H. B. BRYAN.

ELECTRIC MOTOR STARTING AND STOPPING DEVICE.

APPLICATION FILED MAB..14, 1904.

3 SHEETS-SHEET 1.

In l:

No. 788,819. PATENTED MAY 2,1905.

'J..H. B. BRYAN.

ELECTRIC MOTOR STARTING AND STOPPING DEVICE.

APPLICATION FILED 1111.11.14, 1904.

3 SHEETS-SHEET 2.

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4 WIN? U 1 1 No. 788,819. PATENTED MAY 2, 1905. J. H. B. BRYAN.

ELECTRIC MOTOR' STARTING AND STOPPING DEVICE.

APPLIOATION FILED MAR. 14, 1904.

3 SHEETS-SHEET 3,

w www ivo. 788,819.

Patenten May '2, '1905'.

PATENT OEEICE.

JOHN H. B. BRYAN, OF BUFFALO, NEV YORK.

ELECTRIC-MOTOR STARTING AND STOPPING DEVICE.

SPECIFICATION forming part of Letters Patent No. 788,819, dated May 2, 1905.

i Application iiled March-14, 1904. Serial No. 197,920.

To rtl/Z 'Ll/71,071@ it 71mm/ concern:

Be it known that I, JOHN H. B. BRYAN, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented new and useful Improvements in Electric-Motor Starting and Stopping Devices, of which the following' is aspecification.

Induction-motors are usually provided with a starting resistance which is included in the armature circuit or coils by a short-circuiting or resistance switch upon starting' the motors for obtaining' a large starting effort with a limited starting-current. As the motor acquires speed the resistance is gradually cut out by moving the switch in the proper direction. Upon stopping the motor the resistance-switch is moved in the opposite direction for again short-circuiting the resistance preparatory to starting the motor the next time. 1t has been found in practice that attendants upon stopping these motors sometimes neglect to shift the switch, so as to include the resistance in the armature-circuit, thereby causing the fuses to blow out or injuriously heating the motor upon starting the same under full pressure.

The object of this invention is to provide means whereby the resistance is automatically and gradually thrown into and out of operation upon stopping and starting the motor for avoiding the objectionable results mentioned.

In the accompanying drawings, consisting of th ree sheets, Figure 1 is a fragmentary side elevation of my improved motor starting and stopping device. Fig. 2 is a longitudinal section of the actuator for moving the short-circuiting switch of the resistance. Fig. 3 is a sectional View of one of the check-valves controlling the pressure medium to the actuator. Fig. 4 is a horizontal section in line 4 4, Fig. l. Figs. 5 and 6 are vertical sections in lines 5 5 and 6 6, Fig. l. Fig. 7 is a vertical longitudinal section in line 7 7, Fig. 4, showing the reversing-valve for the pressure medium. Fig. 8 is adiagram showing the circuit or wiring of an induction-motor to which my invention is applicable.

Similar letters of reference indicate corresponding parts throughout the several views.

The induction-motor shown in the drawings is of the three-phase type; but my invention is equally applicable to other forms of motors in which avariable resistance is employed for starting the same.

A represents an induction-motor which may be of any suitable and well-known construction and which preferably comprises an armature hav ing its winding divided into a plurality of sections B and a field having its winding divided into a plurality of sections O.

D represents .a switch whereby the motor is connected or disconnected with the main electric conductors or leads E E E and which consists, essentially, of three stationary contacts (Z, connected with the main leads, and three movable contacts or knife-blades d', connected with different sections of the iield and movable into and out of engagement withthe stationary contacts. The switch-blades are pivoted at their corresponding ends on a base F, while their opposite free ends are connected by an insulated cross-bar f, whereby the same may be shifted simultaneously for opening and closing the switch.

The starting resistance is divided into three sections g g g, each of which is connected across one of the armature-winding sections and provided with a movable switch-contact -g, whereby more or less of the resistance may be included in the respective armature-winding section. The contacts g of the several resistance-sections are all mounted on a shifting rod G, whereby these contacts are operated in unison and caused to cut in or cutout the several resistance-sections in the same measure. rlhis rod preferably moves axially in the armature and has one end extending beyond the shaft of the armature, where the same is accessible for manipulation.

My improved starting and stopping device cooperates with the parts of the induction motor just described and is constructed as follows: H represents a power-cylinder arranged on one side of the motor and preferably axially in line therewith. This cylinder is preferably supported by means of arms 71 projecting laterally from'opposite sides thereof, and longitudinal bars L, connecting the ends of the arms with the adjacent side of the IOO motor-frame, as shown in Fig. l. Within the cylinder is a piston which is reciprocatcd therein by alternately connecting opposite ends of the cylinder with a pressure medium and with the atmosphere. This movement of the piston is transmitted to the resistance shifting rod G by a piston-rod which is coupled with the resistance-rod in such manner that the same are compelled to move axially together; but the resistance-rod is free to turn with the armature independently of the piston-rod. As shown in Fig. 2, the piston consists, preferably, of a central disk c', two cup-shaped packings vf, arranged on opposite sides of the central disk, and two outer clamping-disks 'Z2 3, bearing against the outer side of the packings. The piston-rod consists of front and rear sections J J, sliding through stufiing-boxes in the heads /L 7a2 of the cylinder, the front rod-section J being hollow and bearing at its inner end against the front piston-disk v7, while the rear rod-section J bears against the rear piston-disk and is provided with a contracted stem j, passing through the parts of the piston and the hollow front section of the piston-rod. The two sections of the piston-rod are drawn together for clamping the parts of the piston between them by a screw-nut j", applied'to the stem 7' and bearing against the front end of the front pistonseetion. This nutis preferably provided with a handle f2, so that the resistance-switch can be operated by hand when the automatic shifting device gets out of order.

The coupling' between the piston-rod and the resistance-switch rod is preferably constructed as follows: K represents a knob or button secured to the outer end of the resistance-switch rod and turning with the same. This knob is arranged between a head secured to the rear end of the rear piston-rod section and bearing against the front side of the knob,v and a cap t', engaging the rear side of the knob and having a screw connection with the head, as shown in Fig. 2.

While the piston may be actuated by any suitable pressure medium, I prefer for this purpose compressed air, which is supplied by a pipe L. This pipe is provided with a handvalve Zand delivers into the top of a valve case or chest M. The bottom of the valvechest is provided with an exhaust-port Z', leading to the atmosphere, and two inlet or supply ports Z2 Z3, arranged on opposite sides of the exhaust-port and connected with opposite ends of the cylinder by branch pipes m m'. Each of the branch pipes is alternately connected with the air supply and the exhaust by means of a slide-valve N, which reciprocates over the ports, so as to alternately uncover the supply-ports so that they communicate with the air supply and which has a cavity a on its under side which alternately connects the supply-ports with the exhaust-port.

In order to prevent sudden movement of the piston and the resistance-switch, means are provided for checking the movement thereof consisting, preferably, of check-valves O, one of which is arranged in cach branch pipe and opens forwardly for admittingcompressed air to the respective end of the cylinder and by-pass pipes 0', one of which connects the parts of each branch pipe on opposite sides of its check-valve and is provided with a regulating-valve 02. W hen either supply-port is uncovered by the slide-valve, the air entering the respective branch pipe opens the checkvalve therein and flows freely to the respective end of the cylinder, but the check-valve in the other branch pipe is closed, which compels the air exhausting from the opposite end of the cylinder to iiow slowly through the bypass, which is restricted by the regulatingvalve 02, so as to retard the movement of the piston as much as required. By this means quick movement of the resistance-switch in either direction is prevented, which is particularly desirable for gradually cutting out the armature resistance in starting the motor.

In starting the motor the main-line switch is closed first, and then the resistance-switch is shifted to cut out the armature resistance, while in stopping the motor the main-line switch is opened first, and then the resistance switch is shifted for introducing the resistance in the armature. For the purpose of clfecting this relative movement of the main switch and resistance switch the following mechanism is provided: P represents a valverod which is connected at its inner end with the slide-valve and supported at its outer end in a guide i). R represents a reciprocating shipper-rod which is arranged parallel with the valve-rod and guided in ways i'. The shipper rod is provided with a tappet 'if which is arranged between two shoulders or collars r2 frJ on the valve-rod and engages the same alternately for shifting the slide-valve in one direction or the other. S represents a rock-lever having one of its arms connected by a link .s with the shipper-rod, while its other arm is connected with a hand-rod s', whereby the rock-lever is oscillated. This handrod may extend to any convenient place within reach of the attendant. T represents a rockarm which is connected by a link Z with the cross-bar of the main switch. This arm is connected with the rock-lever so as to move with the same during part of its oscillating movement, but is held against movement therewith during the remainder of its oscillating movement. This is preferably effected by means of stops, which limit the rocking movement of said arm, and a frictional or slack coupling between the rock-lever and rock-arm. As shown in Figs. l and 5, the rock-arm is secured to oneend of a rock-shaft U, which is journaled in a standard U, and its rocking movement is limited by means of stops or pins uy u', arranged on the standard in front and in rear IOO IOS

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of the path of the rock-arm. On the opposite end of the rock-shaft the rock-lever is mounted and frictionally secured thereto by a pair of friction-disks o o, arranged on the shaft on opposite sides of the rock-lever, a clamping-disk fu', fixed on the shaft and bearing against one of the friction-disks, a loose clamping-disk o2, bearing against the other friction-disk and connected by a spline o1' key o3 with the shaft, and a clamping-screw nut fn", arranged on the shaft and bearing against the loose clamping-disk, as shown in Fig. 5. For

convenience the several parts of the main switch, the slide-valve, the guides for supporting the sliding rods, and the standard for the rock-shaft are mounted on a bracket W, which is suitably construct-ed for that purpose, as shown in Figs. l and 1f.

/Vhen the motor is running, the rock-lever is in its forward position, the rock-arm engages the front stop a, the switch D is closed, the piston is moved forwardly and the shortcireuiting switch is shifted forward for cutting out the armature resistance, this position of the parts being indicated in Figs. l, 2, if, 7 and 8. /Vhen it is desired to stop the motor, the hand-rod is pulled in the direction of Ythe arrow, Fig. 1. During the first part of this movement the rock-lever and rock-arm turn together until the latter is arrested by engaging the rear stop u, and thereafter the rocklever continues and effects the final part of its movement independent of the rock-arm, this being permitted b y the frictional connection between the rock-lever and arm. While the rock lever and arm are moving forward together the main switch-blades are moved away from their coperating stationary contacts, thereby opening the main switch and cutting off the motor from the main lines. At the same time that the main switch is being opened the shipper-rod is moved forward, and the tappet r is moved idly from the rear collar yri toward the front collar frz. During the continued forward movement of the rock-lever after the main switch has been opened the tappet engages the collar r2 and moves the valverod from the position shown in full lines to the position shown in dotted lines, Fig. 7. The spent air is now exhausted from the front or outer end of the cylinder, and the compressed air is admitted to the rear end of the cylinder, thereby moving the piston backwardly or outwardly and shifting the shortcircuiting switch so as to include the resistance in the coils of' the armature.

When it is desired to start the motor, the hand-rod is moved in the direction opposite to the arrow in Fig. l, during which movement the rock lever and arm move together until the main switch is closed, at which time the rock-arm engages the front stop u and is arrested while the rock-lever continues its forward movement. During the movement of the rock-lever with the rock-arm for closing the main switch the tappet moves idly from the front collar 'r2 toward the rear collar fri; but after the main switch has been closed and the rock-lever continues its forward movement independently of the rock-arm the tappet engages the rear collar r3 and pushes the valve-rod in the direction for shifting the slide-valve from the position shown in dotted lines to the position shown in full lines, Fig. 7, whereby the compressed air is admitted to the front end of the cylinder and exhausted from the rear end thereof, thereby moving the piston inwardly, together with the shortcircuiting switch, and cutting out the resistance from the armature-winding.

By the use of my improved starting device it is impossible to blow out the fuses w or to otherwise injure or derange the motor, as the shifting of the main switch and the resistanceswitch always follow one after the other in the proper manner and at the proper speed, this being effected automatically and wholly regardless of the speed with which the attendant moves the hand-rod into an operative or inoperative position.

inasmuch as the air-pressure is constantly operating against one side or the other of the piston, the resistance-switch is firmly held either in its operative or inoperative position, and accidental displacement of the switch is therefore prevented. In my improved motor starting and stopping' device the switch and slide-valve may be arranged varying distances from the power cylinder and piston which operate the resistance-switch, thus making the same especially desirable for controlling a motor which is elevated or is otherwise located beyond convenient reach or remote from the place where the attendant is located.

While I prefer to mount the starting resistance on the armature of the motor, the same eHect may be obtained by arranging the resistance elsewhere. It is also immaterial whether the starting resistance is arranged in the primary or the secondary circuit.

I claim as my invention4 1. The combination with an induction-inotor and a starting resistance for the same, of a switch for controlling said resistance, a power-cylinder containing a piston which is connected with said switch, conduits for supplying a pressure medium to opposite ends of said cylinder, a check-valve arranged in each of said conduits and operating' to permit the pressure medium to move only forwardly through the same, and a restricted by-pass connecting each of said conduits on opposite sides of its check-valve, substantially as set forth.

2. The combination with an induction-motor and a starting resistance for the same, of a main switch for controlling the connection of the motor with the main lines, a resistanceswitch for controlling said resistance, and a frictional connection between the operating TOO ITS

devices of said switches, substantially as set forth.

3. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance rotating with the armature, a piston connected with said switch, and a power-cylinder in which said piston reciprocates, substantially as set forth.

4. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance rotating with the armature, a piston connected with said switch so as to compel the same to move axially together but permitting the switch to rotate with the armature independently of the piston, and a power-cylinder in which said piston reciprocates, su bstantially as set forth.

5. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance rotating with the armature, a piston connected with said switch so as to compel the same to move axially together but permitting the switch to rotate with the armature independently of the piston, a power-cylinder in which said piston reciprocates, and means for connecting opposite ends of the cylinder alternately with a pressure-supply and with an eX- haust, substantially as set forth.

6. The combination with an induction-motor having its armature provided with a resistance and a switch controlling said resistance and rotating with the armature, of a powercylinder, a piston arranged in the cylinder, and a coupling' connecting the piston and switch and comprising a knob connected with the switch, a head connected with the piston and engaging one side of said knob, anda cap connected with said head and bearing against the opposite side of said knob, substantially as set forth.

7. The combination with an induction-motor having its armature provided with a resistance and a switch controlling' said resistance and rotating with the armature, of a powercylinder, a piston arranged in the cylinder and composed of a central disk, packings arranged on opposite sides of the central disk and clamping-disks bearing against the outer side of the packings, and a piston-rod connecting the piston with said switch and composed of a tubular section engaging one of the clamping-disks and passing through the adjacent head of the cylinder, a solid section bearing against the other clamping-disk and passing through the other head, a stem formed on the solid pistonrod section and passing through the piston and the tubular piston-rod section, and a screwnut arranged on the stem and bearing against said hollow section, substantially as set forth.

8. The combination with an induction-motor having its armature provided with a resistance and switch controlling' said resistance and rotating with the armature, of a powercylinder having arms, bars connecting said arms and the stationary part of the motor, and a piston arranged in the cylinder and operatively connected with said switch, substantially as set forth.

9. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling' said resistance, a power-cylinder containing a piston which is connected with said switch, and a valve constructed to connect opposite ends of the cylinder alternately with a pressure-sup-- ply and an exhaust, substantially as set forth.

10. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance, a power-cylinder containing a piston which is connected with said switch, a valvechest connected with a pressure-supply and having an exhaust-port and two inlet-ports connected with opposite ends of the cylinder, and a valve for connecting either of said inletports with the pressure-su pply or with the cxhaust-port, substantially as set forth.

11. The combination with an induction-inotor having its armature provided with a resistance, 0f a switch for controlling said resistance, va power-cylinder containing a piston which is connected with ,said switch, a valvechest connected with a pressru'e-supply and having an exhaust-port and two inlet-ports, a conduit connecting each of said inlet-ports with one end of the cylinder, a forwardlyopening check-valve arranged in each of said conduits, and a restricted by-pass connecting each conduit on opposite sides of its checkvalve, substantially as set forth.

12. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance, a power-cylinder containing a piston which is connected with said switch, a valvechest connected with a pressure-supply and having an exhaust-port and two inlet-ports, a conduit connecting each of said inlet-ports with one end of the cylinder, a forwardlyopening check-valve arranged in each of said conduits, a restricted by-pass connecting cach conduit on opposite sides of its check-valve, and a regulating-valve arranged in each bypass, substantially as set forth.

13. The combination with an induction-motor having its armature provided with a resistance, of a switch for controlling said resistance, a power-cylinder containing a piston which is connected with said switch, a valve controlling the supply of pressure medium into opposite ends of the cylinder, a valve-rod connected with the valve and having two shoulders, and a reciprocating shipper-rod having a tappet arranged to alternately engage said shoulders for reversing the valve, substantially as set forth.

14. The combination with an induction-mo- IOO TIO

tor having its armature provided with a resistance, of a switch for controlling said resistance, a power-cylinder containing a piston which is connected with said switch, a valve controlling the supply of pressure medium into opposite ends of the cylinder, a valverod connected with the valve and having two shoulders, a reciprocating shipper-rod having a tappet arranged to alternately engage said shoulders for reversing the valve, and a rocklever having one of its arms connected by a link with the shipper-rod while its opposite arm is connected with a hand-rod, substantially as set forth.

15. The combination with an induction-motor having its armature provided with a resistance, of a main switch for connecting and disconnecting the motor with the main lines, a resistance-switch for controlling said resistance, means for shifting the main switch, means for shifting the resistance-switch, and a frictional connection between the shifting means of the main and resistance switches, substantially as set forth.

16. The combination with an induction-motor having its armature provided with a resistance, of a main switch for connecting and disconnecting the motor with the main lines, a

lresistance-switch for controlling said resistance, an actuating device for said resistanceswitch, a rock-lever positively connected with said actuating device, a rock-arm connected with the main switch, and a frictional coupling between the rock-lever and rock-arm,

5 substantially as set forth.

17. The combination with an induction-motor having its armature provided with a resistance, of a main switch for connecting and disconnecting the motor with the main lines, a resistance-switch for controlling said resistance, an actuating device for said resistanceswitch, a rocklever positively connected with said actuating device, a rock-arm connected with the main switch, a frictional coupling between the rock lever and arm, and stops which limit the movement of said arm with said lever, substantially as set forth.

18. The combination with an induction-motor having its armature provided with a resistance, of a main switch for connecting and disconnecting the motor with the main lines, a resistance-switch for controlling said resistance, an actuating device for said resistanceswitch, a rock-lever positively connected with said actuating device, a rock-arm connected with the main switch, a rock -shaft upon which the rock-lever is mounted loosely and to which the rockarm is positively connected, friction-disks bearing against opposite sides of the rock-lever, clamping-disks bearing against the outer side of the frictiondislrs, one of the clamping-disks beingl rigid on the shaft while the other is keyed thereon, and a screw-nut arranged on. the shaft and bearing against the keyed clamping-disk, substantially as set forth.

fitness my' hand this 8th day of March,

JOHN H. B. BRYAN. Witnesses:

Timo. L. Pori), JOHN D. SQUIREs. 

